In conventional cooking appliances, one or more burners are disposed on a cooktop surface of the cooking appliance. For example, FIG. 1 shows a conventional household cooking appliance 10 having a housing 12 and a cooktop surface 14. The cooktop surface 14 includes a plurality of burners 20. The housing 12 supports a grate 26 to support a cooking utensil, such as a pot, pan or kettle over the burner 20. The cooktop surface 14 has a plurality of openings (not shown) defining the positions for each of the burners 20. The cooktop surface 14 shown in FIG. 1 has a sealed burner arrangement.
Although burners for controlling gas flow and flame generation in a cooking appliance have been known, a recent development improves flame spreading features within a controlled area so that the burner does not create a limited set of rings of heat application to a cooking utensil. For example, U.S. application Ser. No. 08/955,002 discloses a multiple fingered burner that expands the heating zone without exposing the peripheral ports in the fingers to exposure from spills occurring above the cooktop. The multiple fingered burner increases or maximizes a perimeter of the burner while also providing more consistent heating of a cooking utensil across the heating zone. That is, the multiple fingered burner expands the heating zone to be more consistent over the perimeter and central zones of the cooking utensil.
While such an arrangement improves distribution of the flames within a cooktop area, recent developments have attempted to further improve access to primary and secondary air in order to maintain appropriately sized flame kernels throughout the irregular pattern of flame kernels throughout the cooktop area, and particularly when a sealed burner arrangement is provided.
Additionally, recent cooktop innovations have attempted to maintain a low profile burner so as not to expose a protruding, interfering surface above the cooktop surface of the appliance. However, the lowering of the burner in the cooktop also may interfere with the free flow of secondary air near the burner ports that receive and discharge a primary fuel and air mixture. In addition, the conventional cooktop designs that provide sealed burner openings may restrict access to secondary air within the appliance and prevent the use of this air as secondary bypass air near the burner ports.
Some conventional appliances attempt to improve access to secondary air for flame production while also minimizing the height of the burner with respect to the cooktop surface. Referring to FIGS. 2A-2D, in some conventional appliances, the cooktop surface 14 includes a “volcano-type” pedestal 30 that is integrally formed with the cooktop surface 14 to elevate the burner 20 above the cooktop surface 14. The burner 20 may be a circular or oval burner, a multiple fingered burner, or other burner. This arrangement may improve access to secondary air for flame production. The integral “volcano-type” pedestal 30 commonly is stamped or formed in the material of the cooktop surface 14 of the appliance. The “volcano-type” pedestal 30 commonly mimics the shape of the burner 20 to provide support for the burner 20. Also, the size of the “volcano-type” pedestal 30 commonly is greater than or equal to the size of the burner 20.
In other conventional systems, the burner may include a pedestal, either separate or integral, to elevate the burner above the cooktop surface. Conventionally, the pedestal has a shape that corresponds to, or mimics, the shape of the burner. Also, the size of the pedestal is greater than or equal to the size of the burner to provide support for all areas of the burner.